1. Technical Field
Example embodiments of the present invention relate to an etchant for a metal layer including copper or a copper alloy, a method of manufacturing a display substrate using the etchant and a display substrate. More particularly, example embodiments of the present invention relate to an etchant for a metal layer including copper or copper alloy, which may be used in a manufacturing process for a display substrate, a method of manufacturing a display substrate using the etchant and a display substrate.
2. Description of the Related Art
Generally, a display panel includes a display substrate including a thin-film transistor as a switching element for driving a pixel. The display substrate may include a plurality of metal patterns, which are generally formed through a photolithography process. According to the photolithography process, a photoresist layer is formed on a film, which is an object of etching, and the photoresist layer is exposed to light and developed to form a photoresist pattern, and the film is etched by an etchant through the photoresist pattern as an etch-stopping layer.
When the film, which is an object of etching, includes copper, an etchant for the film may include a peroxide etchant and a non-peroxide etchant. The peroxide etchant may cause an explosion due to a chemical reaction caused when the peroxide etchant etches the film including copper. When the conventional non-peroxide etchant is used, a cumulative amount of etched films may be small. Furthermore, the conventional non-peroxide etchant may have a low storage stability at a room temperature, and the composition of the non-peroxide etchant may need to be changed depending on the thickness of the film.